Search engine expert Danny Sullivan reviews the search engines of the past and present, with some hints for what is to come, on Clickz.

It’s easy to forget, in this Google-centric universe, how many search engines there have been, and how ruthlessly Darwinian was the process that led to the current situation.

I was surprised by the degree and speed of the consolidation in the business over the last five years, probably because I underestimated the cost of upgrading and maintaining a working search engine relative to the (short term) costs of simply buying the results. The trend toward paid listings will no doubt hasten consolidation because it requires a very new kind of selling infrastructure.

However, the sheer number of players and the low (in absolute terms) price of doing it yourself drive down the value of even a consolidated property.That’s what former high-flyer Inktomi discovered and what Overture is discovering.